I can fit into that class, but I'm a little mystified by it. I don't think the servo timing "standard" says anything about degrees. Just 900ms to 2100ms with a center at 1500ms. The mapping to degrees depends on the service and how far it swings, typically less than 180 degrees. If they went 180 degrees like the wiring docs say they would bind in your typical RC airplane pushrod application.
The gibberish that passes for spec sheets at Hitec seem to say the ones I'm testing with go 60 degrees each way for a 120 degree swing, or maybe 40 each way but I think it is going further than that in my test rig.
Unless someone shows up with knowledge, I guess I'll just make the input go 0 to 180, map that to full swing output and ignore the fact that it isn't really degrees.
The read() method will have to return the result of the last write(), the actual position is not available.